<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>文本格式化</title>
</head>
<body>
<b>This text is bold</b>
<br/>
<strong>This text is strong</strong>
<br/>
<big>This text is big</big>
<br/>
<em>This text is emphasized</em>
<br/>
<i>This text is italic</i>
<br/>
<small>This text is small</small>
<br/>
This text contains
<sub>subscript</sub>
<br/>
This text contains
<sup>superscript</sup>
</body>
</html>